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DSB AM Modulator Passband - Modulate using double-sideband amplitude modulation

Library

Analog Passband Modulation, in Modulation

Description

The DSB AM Modulator Passband block modulates using double-sideband amplitude modulation. The output is a passband representation of the modulated signal. Both the input and output signals are real sample-based scalar signals.

If the input is u(t) as a function of time t, then the output is

where:

• k is the Input signal offset parameter.

• f_c is the Carrier frequency parameter.

• θ is the Initial phase parameter.

It is common to set the value of k to the maximum absolute value of the negative part of the input signal u(t).

Typically, an appropriate Carrier frequency value is much higher than the highest frequency of the input signal. By the Nyquist sampling theorem, the reciprocal of the model's sample time (defined by the model's signal source) must exceed twice the Carrier frequency parameter.

This block works only with real inputs of type double. This block is not suited to be placed inside a triggered subsystem.

Dialog Box

Input signal offset

The offset factor k. This value should be greater than or equal to the absolute value of the minimum of the input signal.

Carrier frequency (Hz)

The frequency of the carrier.

Initial phase (rad)

The initial phase of the carrier.

Pair Block

DSB AM Demodulator Passband

See Also

DSBSC AM Modulator Passband, SSB AM Modulator Passband

DSB AM Demodulator Passband

DSBSC AM Demodulator Passband

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